Si_3N_4/BAS复相陶瓷材料制备及其性能  

Preparation and Performance of Si_3N_4/BAS Composite Ceramics

作　　者：余娟丽[1] 吕毅[1] 王涛[1] 张剑[1] 张天翔[1] 赵英民[1] 裴雨辰[1] 

机构地区：[1]航天特种材料及工艺技术研究所,北京100074

出　　处：《硅酸盐学报》2017年第3期378-383,共6页Journal of The Chinese Ceramic Society

摘　　要：采用新型冷冻胶凝陶瓷成型技术制备高性能Si_3N_4/BAS复相陶瓷透波材料,对Si_3N_4/BAS复相陶瓷材料烧结体成分、力学性能、微观形貌、电性能及抗热震性等进行研究。结果表明:坯体成型收缩率小于1%,在温度升到1 300℃高温时,Si_3N_4/BAS复相陶瓷烧结体弯曲强度280 MPa,弹性模量为90 GPa,介电常数变化率仅为6%。该复相陶瓷材料具有良好的抗热震性能及可加工性,BAS陶瓷玻璃相高温高黏度特性对Si_3N_4/BAS复相陶瓷材料抗热震是一种热应力缓释方式。Si3N4/BAS ceramic composite was prepared by a novel freeze-gelation method. The ceramic composition and micro morphology were analyzed, and the mechanical/electric performance and thermal shock resistance were investigated. The results show that the shrinkage rate of green body is 〈 1%, and the flexural strength, elastic modulus and the change rate of dielectric constant are 280 MP, 90 GPa, 6% at 1 300 ℃, respectively. Si3N4/BAS ceramic composite has a superior thermal shock resistance and a high machinability. At a high temperature, softening and high viscosity of BAS glass phase in Si3N4/BAS ceramic composite are the main reasons of releasing thermal stress.

关 键 词：冷冻凝胶 氮化硅 复相陶瓷 天线罩 

分 类 号：TM28[一般工业技术—材料科学与工程]